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991.
Bordiec S Paquis S Lacroix H Dhondt S Ait Barka E Kauffmann S Jeandet P Mazeyrat-Gourbeyre F Clément C Baillieul F Dorey S 《Journal of experimental botany》2011,62(2):595-603
Plant growth-promoting rhizobacteria (PGPR) are beneficial microorganisms that colonize the rhizosphere of many plant species and confer beneficial effects, such as an increase in plant growth. PGPR are also well known as inducers of systemic resistance to pathogens in plants. However, the molecular mechanisms involved locally after direct perception of these bacteria by plant cells still remain largely unknown. Burkholderia phytofirmans strain PsJN is an endophytic PGPR that colonizes grapevine and protects the plant against the grey mould disease caused by Botrytis cinerea. This report focuses on local defence events induced by B. phytofirmans PsJN after perception by the grapevine cells. It is demonstrated that, after addition to cell suspension cultures, the bacteria were tightly attaching to plant cells in a way similar to the grapevine non-host bacteria Pseudomonas syringae pv. pisi. B. phytofirmans PsJN perception led to a transient and monophasic extracellular alkalinization but no accumulation of reactive oxygen species or cell death were detected. By contrast, challenge with P. syringae pv. pisi induced a sustained and biphasic extracellular alkalinization, a two phases oxidative burst, and a HR-like response. Perception of the PGPR also led to the production of salicylic acid (SA) and the expression of a battery of defence genes that was, however, weaker in intensity compared with defence gene expression triggered by the non-host bacteria. Some defence genes up-regulated after B. phytofirmans PsJN challenge are specifically induced by exogenous treatment with SA or jasmonic acid, suggesting that both signalling pathways are activated by the PGPR in grapevine. 相似文献
992.
Yous S Durieux-Poissonnier S Lipka-Belloli E Guelzim H Bochu C Audinot V Boutin JA Delagrange P Bennejean C Renard P Lesieur D 《Bioorganic & medicinal chemistry》2003,11(5):753-759
Tetrahydronaphthalenic analogues of melatonin have been synthesized and evaluated as melatonin receptor ligands. Introduction of a phenyl substituent in the 3-position of the tetraline ring allows to obtain MT(2) selective ligands. Activity and MT(2) selectivity can be modulated with suitable modifications of the N-acyl substituent. The (+)-(RR)-cis enantiomer of the N-[2-(7-methoxy-3-phenyl-1,2,3,4-tetrahydro-naphthalen-1-yl)ethyl]cyclobutyl carboxamide (14) is one of the most MT(2) selective ligands described until now and behaves as an antagonist. 相似文献
993.
Immune memory has traditionally been the domain of the adaptive immune system, present only in antigen‐specific T and B cells. The purpose of this review is to summarize the evidence for immunological memory in lower organisms (which are not thought to possess adaptive immunity) and within specific cell subsets of the innate immune system. A special focus will be given to recent findings in both mouse and humans for specificity and memory in natural killer (NK) cells, which have resided under the umbrella of innate immunity for decades. The surprising longevity and enhanced responses of previously primed NK cells will be discussed in the context of several immunization settings. 相似文献
994.
Damien Drubay Sophie Ancelet Alain Acker Michaela Kreuzer Dominique Laurier Estelle Rage 《Radiation and environmental biophysics》2014,53(3):505-513
The investigation of potential adverse health effects of occupational exposures to ionizing radiation, on uranium miners, is an important area of research. Radon is a well-known carcinogen for lung, but the link between radiation exposure and other diseases remains controversial, particularly for kidney cancer. The aims of this study were therefore to perform external kidney cancer mortality analyses and to assess the relationship between occupational radiation exposure and kidney cancer mortality, using competing risks methodology, from two uranium miners cohorts. The French (n = 3,377) and German (n = 58,986) cohorts of uranium miners included 11 and 174 deaths from kidney cancer. For each cohort, the excess of kidney cancer mortality has been assessed by standardized mortality ratio (SMR) corrected for the probability of known causes of death. The associations between cumulative occupational radiation exposures (radon, external gamma radiation and long-lived radionuclides) or kidney equivalent doses and both the cause-specific hazard and the probability of occurrence of kidney cancer death have been estimated with Cox and Fine and Gray models adjusted to date of birth and considering the attained age as the timescale. No significant excess of kidney cancer mortality has been observed neither in the French cohort (SMR = 1.49, 95 % confidence interval [0.73; 2.67]) nor in the German cohort (SMR = 0.91 [0.77; 1.06]). Moreover, no significant association between kidney cancer mortality and any type of occupational radiation exposure or kidney equivalent dose has been observed. Future analyses based on further follow-up updates and/or large pooled cohorts should allow us to confirm or not the absence of association. 相似文献
995.
Fabrizio De Vico Fallani Jonas Richiardi Mario Chavez Sophie Achard 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1653)
The brain can be regarded as a network: a connected system where nodes, or units, represent different specialized regions and links, or connections, represent communication pathways. From a functional perspective, communication is coded by temporal dependence between the activities of different brain areas. In the last decade, the abstract representation of the brain as a graph has allowed to visualize functional brain networks and describe their non-trivial topological properties in a compact and objective way. Nowadays, the use of graph analysis in translational neuroscience has become essential to quantify brain dysfunctions in terms of aberrant reconfiguration of functional brain networks. Despite its evident impact, graph analysis of functional brain networks is not a simple toolbox that can be blindly applied to brain signals. On the one hand, it requires the know-how of all the methodological steps of the pipeline that manipulate the input brain signals and extract the functional network properties. On the other hand, knowledge of the neural phenomenon under study is required to perform physiologically relevant analysis. The aim of this review is to provide practical indications to make sense of brain network analysis and contrast counterproductive attitudes. 相似文献
996.
Laure Frésard Sophie Leroux Bertrand Servin David Gourichon Patrice Dehais Magali San Cristobal Nathalie Marsaud Florence Vignoles Bertrand Bed'hom Jean-Luc Coville Farhad Hormozdiari Catherine Beaumont Tatiana Zerjal Alain Vignal Mireille Morisson Sandrine Lagarrigue Frédérique Pitel 《Nucleic acids research》2014,42(6):3768-3782
997.
Fabien Sénéchal Lucile Graff Ogier Surcouf Paulo Marcelo Catherine Rayon Sophie Bouton Alain Mareck Gregory Mouille Annick Stintzi Herman H?fte Patrice Lerouge Andreas Schaller Jér?me Pelloux 《Annals of botany》2014,114(6):1161-1175
Background and Aims
In Arabidopsis thaliana, the degree of methylesterification (DM) of homogalacturonans (HGs), the main pectic constituent of the cell wall, can be modified by pectin methylesterases (PMEs). In all organisms, two types of protein structure have been reported for PMEs: group 1 and group 2. In group 2 PMEs, the active part (PME domain, Pfam01095) is preceded by an N-terminal extension (PRO part), which shows similarities to PME inhibitors (PMEI domain, Pfam04043). This PRO part mediates retention of unprocessed group 2 PMEs in the Golgi apparatus, thus regulating PME activity through a post-translational mechanism. This study investigated the roles of a subtilisin-type serine protease (SBT) in the processing of a PME isoform.Methods
Using a combination of functional genomics, biochemistry and proteomic approaches, the role of a specific SBT in the processing of a group 2 PME was assessed together with its consequences for plant development.Key Results
A group 2 PME, AtPME17 (At2g45220), was identified, which was highly co-expressed, both spatially and temporally, with AtSBT3.5 (At1g32940), a subtilisin-type serine protease (subtilase, SBT), during root development. PME activity was modified in roots of knockout mutants for both proteins with consequent effects on root growth. This suggested a role for SBT3.5 in the processing of PME17 in planta. Using transient expression in Nicotiana benthamiana, it was indeed shown that SBT3.5 can process PME17 at a specific single processing motif, releasing a mature isoform in the apoplasm.Conclusions
By revealing the potential role of SBT3.5 in the processing of PME17, this study brings new evidence of the complexity of the regulation of PMEs in plants, and highlights the need for identifying specific PME–SBT pairs. 相似文献998.
Carlos Castro-González Miguel A. Luengo-Oroz Louise Duloquin Thierry Savy Barbara Rizzi Sophie Desnoulez René Doursat Yannick L. Kergosien María J. Ledesma-Carbayo Paul Bourgine Nadine Peyriéras Andrés Santos 《PLoS computational biology》2014,10(6)
A gene expression atlas is an essential resource to quantify and understand the multiscale processes of embryogenesis in time and space. The automated reconstruction of a prototypic 4D atlas for vertebrate early embryos, using multicolor fluorescence in situ hybridization with nuclear counterstain, requires dedicated computational strategies. To this goal, we designed an original methodological framework implemented in a software tool called Match-IT. With only minimal human supervision, our system is able to gather gene expression patterns observed in different analyzed embryos with phenotypic variability and map them onto a series of common 3D templates over time, creating a 4D atlas. This framework was used to construct an atlas composed of 6 gene expression templates from a cohort of zebrafish early embryos spanning 6 developmental stages from 4 to 6.3 hpf (hours post fertilization). They included 53 specimens, 181,415 detected cell nuclei and the segmentation of 98 gene expression patterns observed in 3D for 9 different genes. In addition, an interactive visualization software, Atlas-IT, was developed to inspect, supervise and analyze the atlas. Match-IT and Atlas-IT, including user manuals, representative datasets and video tutorials, are publicly and freely available online. We also propose computational methods and tools for the quantitative assessment of the gene expression templates at the cellular scale, with the identification, visualization and analysis of coexpression patterns, synexpression groups and their dynamics through developmental stages. 相似文献
999.
1000.
The negative implications of living in a socially unequal society are now well documented. However, there is poor understanding of the pathways from specific environmental risk to symptoms. Here we examine the associations between social deprivation, depression, and psychotic symptoms using the 2007 Adult Psychiatric Morbidity Survey, a cross-sectional dataset including 7,353 individuals. In addition we looked at the mediating role of stress, discrimination, trust and lack of social support. We found that the participants'' neighbourhood index of multiple deprivation (IMD) significantly predicted psychosis and depression. On inspection of specific psychotic symptoms, IMD predicted paranoia, but not hallucinations or hypomania. Stress and trust partially mediated the relationship between IMD and paranoid ideation. Stress, trust and a lack of social support fully mediated the relationship between IMD and depression. Future research should focus on the role deprivation and social inequalities plays in specific manifestations of psychopathology and investigate mechanisms to explain those associations that occur. Targeting the mediating mechanisms through appropriate psychological intervention may go some way to dampen the negative consequences of living in an unjust society; ameliorating economic injustice may improve population mental health. 相似文献